Wrong alignment for m68k pointer types

[antoyo]

I'm working on making the libcore tests pass for m68k on rustc_codegen_gcc.

It looks like LLVM rust uses the SysV ABI for m68k, but it says the alignment for pointer types is 2, while this doc says it should be 4.

Also, this test fails.

It also says the alignment of usize/isize is 2.

cc @glaubitz

[lukas-code]

Also, this test fails.

Yea that test is just wrong, it needs explicit alignment like in the core docs.

[antoyo]

There are other test failures:

test mem::offset_of ... FAILED
test mem::align_of_32 ... FAILED
test mem::align_of_basic ... FAILED
test mem::align_of_val_basic ... FAILED

so I'm assuming this test might be wrong as well.

(I also have a few float tests failing, but that might be because of how I handled them. I'll investigate.)

[glaubitz]

Thanks for catching this. The unusual default alignment on m68k is regularly causing problems.

We're actually planning to switch default alignment on Debian and Gentoo to 32 bits for m68k.